Fuse-plug



H. I'. PAISIE.

FUSE PLUGl APPLICATION FILED nIEc.2I, I9I7.

Patented Aug. 17, 1920.

UNITED STATES PATENT OFFICE.

HENRY T. PAISTE, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOB TO H. T. PAISTE COMPANY, VAN IA.

0F PHILADELPHIA, PENNSYLVANIA, A CORPORATION OF PENNSYL- FUSE-PLUG.

Specification of Letters Patent.

Patented-Aug. 17, l1920.

Application led December 21, 1917. Serial No. 208,301.`

T0 all whom, t may concern:

Be it known that I, HENRY T. PAIsTE, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented Fuse-Plugs, of which the following is a specification.

This invention relates to a form of fuse plug having two separable parts of which one carries a fuse in such manner as to permit of its convenient renewal, one object of said invention being to provide a compact, substantial and conveniently operable plug of' the type noted.

It is further desired to p rovide a two-part fuse plug of such construction that relative rotation of its parts is effectually prevented while at the same time good electrical contact between the fuse proper and certain conducting elements of the plug is assured.

Another' object of the invention is to provide a novel form of fuse-carrying element for a two-part fuse plug, whose parts shall be so arranged and constructed as to permit of the rapid and convenient insertion of a length of fuse wire in one of said parts.

It is also desired to provide a novel form of fuse body including novel means for detachably engaging the screw or other' holding member forming a part of the fuseholding element with a view to mechanically connecting said body and clement as well as insuring good electrical contact between a length of fuse wire or strip and certain terminals respectively on the body and said element.

These objects and other advantageous ends l attain as hereinafter set forth, reference being had to the accompanying drawings, in which:

Figures 1 and 2, are respectively a side elevation and a plan of a fuse plug constructed according to my invention.

Fig. 3, is a vertical section on the line 23H3, Fig. 2,

Figs. 4 and 5 are perspective, views of the fuse-carrying element of the plug, with the central terminal removed, and

Figs. 6 to 12 inclusive, are perspective views of various parts of the plug.

In the above drawings, 1 represents a fuse plug body preferably made of a vitreous material such as porcelain and consisting of a hollow cylindrical portion 2 having an outwardly extending flange 3 at one end. The passage through the portion 2, While of any section other than circular, is shown in the present instance as of hexagonal outline which within the Harige 3 merges into a cavity of circular section, whose walls at two opposite points, are formed to provide rectangular recesses 4. The outer face of the flange 3 is provided with a series of radial grooves and its lower edge adjacent the portion 2 is also formed with grooves 6.

The inner edge of said flange 3 is slightly depressed, as indicated at 7, to provide a shoulder for the support of a circular mica plate 8, which is held in position to close the flanged end of the body by means of an inwardly flanged ring 9 of sheet metal which extends down around the sides of the flange 3 and is turned inwardly as shown at 10 so that it is permanently held to the body 1. Said mica plate and retaining ring serve to permanently retain in place a metal bridge piece 11 of channel section which extends dia metrically across the opening through the flange 3 and has its ends fitted in the recesses al. in the walls thereof. This bridge piece has a central threaded opening 12 for the reception of a screw 13 hereafter referred to.

Mounted upon the cylindrical outer surface of the part 2 of the body is a threaded shell 14 of sheet metal having the general forni of an Edison socket or lamp terminal and made with its inner edge 15 turned in so as to project into an angular groove 16 formed in the part 2 of the body adjacent the flange 3, while the opposite end of said part is spun or otherwise turned over the end of said part 2 as indicated at 17, having through it a hexagonal or other opening of the same outline as that of the passage through the fuse body.

The second member of thc fuse plug consists in the present instance of a hexagonal prismatic piece 18 having at one end an outwardly extending flange 19 and made of porcelain or other insulating material the same as that of the body 1. The outer face of' the flange 19, while generally convex in form, is provided with a centrally placed circular depression 20 concentric with a passage or hole 21 extending axially through said part 18 while at one side of this central hole, is a second and usually smaller passage extending parallel to it through the piece 18 to that end thereof distant from the flange 19 where it opens adjacent a shoulder 22 formed at a level slightly below that of the end 23. rllhis shoulder extends circumlerentially around a greate or less portion of one side oit this end and ata point distantfrom the side passage has opening into it a channel 24rformed in one ot the faces ot the piece 1S, in which it extends preferably, though not necessarily, parallel with thehole 21 to the under tace ot the flange 19. This, ts indicated at 25, is preterably tl'iough not necessarily, radially recessed to `form a continuation oit said channel. il. length olf i'iuse wire 26 haring a circularly curved portion at one end, extends through. the side 'passage of the prisinatic piece 1S in such manner that said curved portion lies within the recess 2O substantially concentric with the hole 21. The op posite end of said luso wire then entends around the end o'i' the capsule over the shoulder` 22 and back toward the ilano'e 19' through the channel 24, being linally bent radially outward in the recess 25and termii'iating slightly inside of the outer edge oi" said flange. A. metal disk 28, preferably having a central threaded opening which is counter sunk on one .tace of said disk and surrounded by a conical collar 2? on the opposite face, is designed to rest on the circularly formed end ot the fuse wire 26 in recess 20, and the screw 13 passes through this disk and the hole 2l into the central hole 12 of the bridge piece 11.

By setting up this screw, goed electrical contact is assured between the terminal dish or plate 28 and the end ot the vfuse wire 26, and it is noted that the same action, by drawing the prismatic block 18 into the iuse plugl body 1, likewise causes the flange 1) to lorcibly press the. outwardly extending end 2G of the fuse wire 'into electrical engagement with the inwardly turned bange 1.7 of the terminal shell 141-, thereby establishing an electrical circuit 'trom theA terminal plate 28 through the fuse wire 2G to the threaded shell `1-t so that the plug may be used in the welldrnown way asa safety dei/'icc for electrical circuits.

ln case o'l an overload in the circ-uit in which it is included, the blowing of the ruse wire would be visible through the mica plate and thereafter in order to replace said broken wire, the screw 13Y is treed from the bridge piece 11 whereupon the fusecariying element or capsule may be removed from the body 1. By withdrawing the screw 13 and thus removing the disk 28 from the recess 20, it is possible to easily withdraw any part of the fuse wire still remaining in said recess or in the passage leading thereto.

A new length of fuse wire may now be placed in the recess, run through the side passage'ot the element 18, across the shoulder 22, down the outside channel 24 and outwardly across the tace ofthe ilanoe 19;- it being noted that the thickness of the fuse wire is greater' than the depth ot the recess 25 in said flange so that good electrical contact ot said end with theilange 17 ot the threaded shell 111 is assured. l

By threading the screw 13 into the Vdisk 28, these parts are held together against accidental separation and possible loss, and by providing the collar 27 on said disk there is obtained an increased contact surface in engagement with the fuse wire 26. ln this case said disk or plate 28 is slightly less in diameter than the recess 20 olf' the fuse capsule 18 so that the under side et said disk is `certainly drawn into engagement with the 'end of the tuse wire when the screw 13 is set up.

@ne important advantage ot the above described construction resides in locking the shell 14 to the body 10 by means ot the capsule or fuse-carrying velement ot other than circular section, and asa result, when the plug as a whole is screwed into or out ot a socket or receptacle, the tendency oiE said shell to stick or resist movement is Veileetually overcome, since the rotative torce ap'- plied by the operator to the part 9 and hence to the body structure 10, is transferred from the latter to the hexagonal or other non-circular capsule structure and thence to the inwardly extending ilano'e 17 ot the shell, which is consequently forced to turn without possibility ot independent movement.

l claim y 1. The combination in a 'fuse plug ot a body; a :fuse-carrying element removably but non-rotatably mounted in said body with its iuse inclosed thereby; terminals respectively on the body and on said element normally connected through the fuse; and a. member extending through the iusecarrying element, echani 'ally and separably connecting it to the body.

2. The combination in a fuse plug ot a body; a ifuse-carrying4 element removably fitting into said body; a screw separably connecting the Vbody and said element; a central terminal on the tosc-carrying olement engaged. by said screw; the 'tuse ol said element extending over a portion of the outside surface thereoil and being electrically connected to said terminal; and a fuse body having va terminal shell' including a portion clamped against the fuse by the action oit said screw. Y

3. The combination in a 'luse Yplug of a body having an opening therethrough; a bridge piece spanning said opening; a fusecarrying element removably fitting the opening et said body; a member extending through saidelement into Vholding engagement with the bridge piece; with terminals respectively on said element and the body electrically connected throughthe fuse ot 'the element.

4. The combination in a fuse plug of a body having an opening therethrough; a bridge piece spanning said opening; a fusecarrying element removably itting the opening of said body; a screw extending through said element into holding engagement with the bridge piece; with terminals respectively on said element and the body electrically connected through the fuse of the element.

5. The combination in a fuse plug of a body having an opening therethrough; a bridge piece spanning said opening; a fusecarrying element removably and non-ro tatably iitting the openingof said body; a member extending through said element into holding engagement with the bridge piece; with terminals respectively on said element and the body electrically connected through the fuse of the element.

G. The combination in a fuse plug of a body ha ing an opening therein; a bridge piece spanning said opening; a block removably fit-ting thc opening of the body; a screw passing through said block and threaded into the bridge piece; a terminal plate held to the block by the screw; a fuse having one end gripped by the said plate to the block and extending through the latter to the outside surface thereof; with a terminal shell on the body and including a portion clamped against the outer part of said fuse by the action of the screw.

'7. The combination in a fuse plug of a body having an opening therethrough; a ln'idge piece spanning said opening adjacent one end thereof; a block of generally prismatie form non-rotatably fitting the opening o'l' the body; a screw extending axially through said block into engagement with the bridge piece; a fuse extending through the block; over one end thereof and thence through an open recess toward the opposite end of the block; a terminal shell on the body having an inwardly extending portion placed to be engaged by an end portion of the fuse when said screw is set up; and a substantially central terminal plate on the block in electrical connection with the second end of the fuse.

8. The combination in a fuse plug of a body having an opening therein; a threaded terminal shell Yon the body having an inturned .liange projecting at one end thereof; a flanged element removably fitting the opening of the body; a fuse having one end extended outwardly over the flange of said element in position to engage the fiange of the terminal shell; a center terminal on the flanged element connected to the fuse; and a member passing through said terminal mechanically and separably connecting the body and said element.

9. As a new article of manufacture a block of insulating material of other than circular cross section; having two parallel passages extending longitudinally through it and also having a groove in its side parallel with said passages; a terminal plate at one end of said block; with a fuse electrically connected to said plate, extending through one of the passages of the block thence back through the groove thereof and then projecting outwardly.

10. As a new article of manufacture a fuse-carrying element consisting of a block of insulating material having a longitudinally extending passage through its body and a groove in its outside surface substantially parallel to said passage, there being a recess at one end of the block connecting the adjacent ends of the passage and groove; a terminal plate at one end of the block; with a fuse electrically connected to said plate, extending therefrom through the passage, thence in the end recess circumferentially of the plug and back through the groove toward the plate-carrying end of the block.

11. As a new article of manufacture a fuse-carrying element consisting of a block of insulating material having a central recess and two longitudinally extending pas sages of which one opens into said recess, there being a groove formed in the outside surface of the block and a recess in the second end of the latter connecting said groove with the non-central passage; a terminal plate mounted in the central recess of the block; with a fuse wire having one end in said .latter recess in electrica-l connection with the plate and extending through the non-central passage of the block, thence through the second-end recess of the block substantially concentric with the central passage and then back toward the opposite end of the block through the groove thereof.

In witness whereof I affix my signature.

HENRY T. PAISTE. 

